Figure 1. A mass on the patient’s left wrist.
A 58-year-old woman presents with complaints of a pea-sized mass on the thumb side of her left wrist. She knits daily and has noticed some mild pain on that side of her wrist over the last few months. The mass has been present for approximately 1 month and persists despite a 3- to 4-week period of thumb immobilization in a brace. On physical examination, the patient has a pea-sized ganglion cyst that appears to be on the extensor pollicis brevis tendon. The cyst moves with extension and flexion of the thumb (Figure 1).
Submit your diagnosis to see full explanation.
A ganglion cyst is the most common tumor of the hand and is 3 times more likely to occur in women compared with men.1 Ganglion cysts can occur on tendons and adhere to the outside of the tendon without affecting function. A flexor tendon sheath ganglion can be diagnosed by the presence of a small mass that moves with the tendon. Aspiration of clear gelatinous fluid helps confirm the diagnosis and rule out other causes such as a giant cell tumor and infection. Magnetic resonance imaging (MRI) and radiographs are not indicated when a flexor tendon ganglion cyst is clinically diagnosed.1,2
The first treatment recommendation is observation; in most cases, the cyst will likely resolve with time. The patient in this case has trialed a period of immobilization that did not improve her case. In this situation, an aspiration is the most appropriate next step. Aspiration with or without steroid injection can be performed if the cyst fails to resolve on its own.1,2
Patients should be warned that skin depigmentation and atrophy can occur with a steroid injection. A single aspiration has a high likelihood of recurrence, while surgical excision is often successful for complete resolution. Surgical excision comes with a higher risk of potential complications (infection, wound healing issues) and, thus, aspiration is recommended before surgery is considered.1,2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor in chief of the Journal of Orthopedics for Physician Assistants.
1. Young L, Bartell T, Logan SE. Ganglions of the hand and wrist. South Med J. 1988;81(6):751-760. doi:10.1097/00007611-198806000-00017
2. Jebson PJ, Spencer EE Jr. Flexor tendon sheath ganglions: results of surgical excision. Hand (NY). 2007;2(3):94-100. doi:10.1007/s11552-007-9028-4